Can someone explain this?

I am trying to modify the following code and I do not understand how it operates.

I have an applet named Test.java that was furnished with a Device Server I purchased. The applet makes a TCP/IP connection then it has the following code:

The manufacturer supplied another program called Text_io.java which sends and receives keyboard characters to and from the Device Server.

I assume the code somehow calls the methods in the Text_io.java program. I don't understand how this works, and I have not been able to find the answer by searching the web. Can someone explain how this works.

The Text.java program uses GridBag to generate some boxes on the page, and the letter "c" is used in this code as such .

For my application I want to remove all the GridBag code and make the applet a zero size applet, yet I want to call the methods in the Text_io.java program. How can I do this?